Today's most interesting conference topic: Plastic. We love it. In 1950, global plastic demand was about 1.7 million tons a year. By 2014, that number was up to 311 million tons. It's super useful - bags, packaging, medical equipment, outdoor gear. You'd be hard pressed to look around you right now and not see any plastic.

And while we find it pretty handy to just throw away that empty plastic water bottle or dried up old pen, that stuff ends up everywhere, slowly breaking down into tinier and tinier pieces but not actually going away. This is proving to be an especially big problem in the ocean, where 13 million tons of plastic made its way in 2010.

Here's a short list of the problems it can cause. Some of these are nothing new - animals caught in soda can rings and or eating plastic bags, for instance - but there are a few that I found surprising:

Entanglement - the aforementioned soda can rings are an example
Ingestion - ditto the aforementioned plastic bags
Vectors for dispersing organisms - because plastic lasts so long and drifts, organisms can attach to it and be carried to new areas.
Toxins that affect animal health - the same crap that's bad for us in plastic (sometimes referred to as Persistent Organic Pollutants - POPs) can also be bad for animals.
Plastic debris on the seafloor - may change the local chemistry and release toxic chemicals

Microplastics - plastic bits less than 5mm in size - are the latest point of concern. These come from the breakdown of plastics or certain fibers (like rayon) into smaller and smaller pieces, and from products like exfoliants and toothpastes that contain microbeads (the US actually just banned these - the new law goes into effect in July 2017).

Microplastics are often mistaken for food by all kinds of aquatic life, from tiny zooplankton to turtles. Sometimes the bits pass through them (I watched a video showing a copepod slurping up dozens of microplastics, and then pooping them out) but the animals can still absorb POPs or have inflammatory responses. Sometimes the particles get lodged in animals' guts, causing health issues, including starvation.

Interestingly, climate change and melting sea ice have an effect on plastic in Arctic waters. As the region warms and becomes more accessible, humans have a bigger footprint - more fishing, more tourists ships making ports of call to places like Longyearbyen, Svalbard - and the currents carry more plastics long-distance from Northern Europe. In fact, the amount of plastic found by Arctic researchers raises the possibility of a sixth garbage patch forming in the Barents Sea, just north of Norway and Russia.